Hi,

Try this

=SUMPRODUCT(SUMIF(INDIRECT(J2:J46&"!D4:D7"),"-9.999E307"))/SUMPRODUCT(COUNTIF(INDIRECT(J2:J46&"!D4:D7"),"-9.999E307"))

D4:D7 holds the sheet names to the summed up - in your case, worksheet 1,
worksheet 2 , worksheet 3 and worksheet 4

--
Regards,

Ashish Mathur
Microsoft Excel MVP
www.ashishmathur.com

"ericaamousseau" wrote in message
...
I can not figure this out! I need to average multiple rows of data in 4
different worksheets. The biggest problem is that the data is calculated
from time differences, so #Value! is common because of using NA instead of
a
time. So say I need J2:J46 in worksheet one J2:J46 in worksheet 2 J2:J46
in
worksheet 3 and J2:J46 in worksheet 4 all averaged together. Also there
will
be some non value numbers. Help!